CombinationRandomSampler does not have __len__ or _num_samples

[tristandeleu]

CombinationRandomSampler does not have __len__ or _num_samples

[tristandeleu]

Thanks for the bug report! Compatibility with other packages is definitely important, especially with something as widely used as pytorch-lightening, and it looks like a great update. A PR would be very appreciated, thank you very much! Another option could also be to call directly len(self.data_source), since CombinationMetaDataset does define __len__.

[gdahia]

I think your suggestion is an improvement over mine, but digging a little deeper, it seems to me that calling super(CombinationRandomSampler, self).__init__(data_source) would solve the problem because RandomSampler defines __len__ in a compatible way.

While I am at it, I could also add error messages to the ValueError when the data_source is not a CombinationMetaDataset. Does that sound good to you? Thanks.

[tristandeleu]

That is indeed a much simpler solution.

While I am at it, I could also add error messages to the ValueError when the data_source is not a CombinationMetaDataset. Does that sound good to you? Thanks.

That would be great, thanks!